White Horse: The 'W' Gene Wonder
It is rather rare to come across a true white horse which carries the White or 'W' gene as most horses that are commonly referred to as being a white horse are in fact gray horses whose hair coats are absolutely white. The white horse is born white and always has a coat that is white in color without any other color being present and it stays white right through its life and usually, the white horse may have blue, brown or hazel eyes.
White and Not Gray
Very often people use the term white for a gray horse due to confusion but the most noticeable difference between the gray horse having a completely white hair coat and a white horse is the color of the skin: the gray horse will be having black skin while the white horse will have pink skin. Whereas the gray horse is born with a dark base coat that may look bay, chestnut or black and it gets lighter with age, its white counterpart is born white and will retain the white coat without any other color present and will stay white all of its life.
There are also horses which are light crème colored and are technically called Crème, cremello or perlino horses and even though the white horse may resemble the light cremello, the origins of the color in terms of genes are different and produce different colors in their sons and daughters. In addition, there are many white horses that are in fact Paints or Pintos which have white markings which are fully or maximum expressed and this refers to the fact that the horse has one big white spot. There are those that claim that the white horse is really a fully-expressed pinto although there are strong indications that the 'W' gene exists independent of any gene in the case of spotting patterns.
The fully expressed whites may exist in any breed with the sabino, Overo or Tobiano gene and it really means that these are horses having white markings so big or plentiful that the whole body of the horse is covered by such spots. The most famous white horse as seen in the movie Lone Ranger went by the name of Silver. In case a white horse is bred with a horse of a different color, there is a 50 percent chance that the offspring will turn out to be white as well while for the remaining 50 percent the chances are that the offspring will have the color of the other parent.